EPN

Agent Name
EPN
Alternative Name
O-Ethyl-O-(4-nitrophenyl)phenylthiophosphonate
CAS Number
2104-64-5
Formula
C14-H14-N-O4-P-S
Major Category
Pesticides
Synonyms
O-Ethyl-O-(4-nitrophenyl)phenylthiophosphonate; O-Ethyl O-(4-nitrophenyl) benzenephosphonothioate; Ethyl p-nitrophenyl benzenethionophosphonate; O-Ethyl-O-(4-nitrophenyl)phenylthiophosphonate;
Category
Organophosphate Insecticides
Description
Yellow solid with an aromatic odor. [pesticide] [Note: A brown liquid above 97 degrees F.] [NIOSH]
Comments
A small number of the organophosphates (OPs) can Induce Delayed Neuropathy (OPIDN). OPIDN usually occurs after ingestion and is usually nonoccupational. [Levy, p. 431] “The average of two baseline respective cholinesterase activity determinations three days apart, with no exposures to enzyme inhibiting pesticides for at least 30 days, is recommended for each worker prior to exposure to cholinesterase inhibitors because of large inter-individual differences in published baseline values. To be established at least once a year. Removal from workplace exposures is recommended until the cholinesterase activity returns to within 20% of baseline.” [TLVs and BEIs]
Restricted
"No ACTIVE registrants found for selected chemical." [NPIRS] Use as mosquito larvicide cancelled in 1983; All registrations voluntarily cancelled in 1987; [EPA: Status of Chemicals in Special Review]
Biomedical References

Exposure Assessment

BEI
Acetylcholinesterase activity in red blood cells = 70% of individual's baseline; Butylcholinesterase activity in serum or plasma = 60% of individual's baseline; Sample at end of shift; [TLVs and BEIs]
Skin Designation (ACGIH)
Yes
TLV (ACGIH)
0.1 mg/m3, inhalable fraction and vapor
PEL (OSHA)
0.5 mg/m3
MAK
0.5 mg/m3, inhalable fraction
IDLH (NIOSH)
5 mg/m3
Vapor Pressure
9.5E-07 mm Hg

Adverse Effects

Neurotoxin
Predominantly motor
ACGIH Carcinogen
Not Classifiable
Other Poison
Organophosphate

Diseases, Processes, and Activities Linked to This Agent

Diseases

Occupational diseases associated with exposure to this agent: